Pros: DURABILITY! Fun, easy to use, lightweight, small and easy to travel with.
Nothing is cooler to a little boy than owning a Nintendo DS Lite and my 5-year old son really loves his! This has not only been entertainment for him, but for the rest of the family as well.
He had a black one before that eventually gave out, they would only play Game Boy games in the Game Boy slot, but not DS games. It's okay since it was a gift for my daughter (his older sister), so it actually went through two kids before giving out. He now has a red one that we bought for him. I will say that 5-year old boys aren't always easy on their DS Consoles, so it's best to keep an eye on it and buy a case for it. We have a padded, zippered case and I've seen other boys with a more durable plastic one (I've seen them for sale at stores like Game Stop, Target, etc.).
We had some construction in our home going on for about a week upstairs and I needed to keep my son away from it all, yet keep an eye on the contractors at the same time. This DS came in handy like no other. We played games on the couch and up to the table together, he just cuddled up to me and we played. It was the only thing that kept him (4 at the time) out of the way of the construction workers.
The DS is very cool, it flips open and fits in one or two little hands quite easily. The unit has the A, Y, X, and B buttons on the right and the directional button on the left (to go up, down, left or right). There is a start and select button.
This DS comes with a stylus pen, which comes in handy for some DS games when fingers won't do the trick. It is made of plastic, so it does not scratch the screen. There is a pen slot in the back that holds the pen, so there is little chances to lose it (you can always purchase more stylus pens separately, but we barely use ours). There is a volume button on the bottom ( you can turn the sound all the way down or up high, and for a little console, it can get loud). It has a place where a child can plug in headphones (this is awesome to use in quiet places like the car, or waiting somewhere public).
I find these little consoles VERY DURABLE. It's been tossed around, banged up and you name it. We like to charge it via the wall outlet plug it came with and I bring the plug (that's detachable) with us when we travel. This DS is awesome for kids when traveling. It makes car rides for restless boys more bearable, just make sure it's charged and you have extra games (and games are not cheap- so I like to buy them used). There is power switch on the side and the DS games slot is in the back. It tells you how to pop the DS games in and out, it says "Push card to eject" on the back. The sticker/picture part of the DS game always points outward (away from the DS) as you put it in, but you will find that out as you cannot put them in backward.
The screen is small, but big enough to see what you're doing. Some games just use one screen, and other games will use two screens (top and bottom screen). You use your fingers to tap the screen or the buttons to start your games. The DS will even display the date and time (which my son loves to look at instead of a calendar or clock). As an adult, I can manage this DS well, as my son even at his young age. It all depends on the games you buy, for instance, he can play Kirby, Mario Kart and Super Mario Bros. quite well, but Sonic isn't so easy for him. I clean the screens with a cloth or paper towel because little sticky fingers make it smeared often. The battery really lasts a very long time, hours (I will admit I've never measured, but it lasts days even of play time). There is a flashing green light on the front/top area that tells you the battery is good and turns red when you need to charge it. You can watch movies as well and/or the movies in the beginning of the DS games (which is quite cool- it reminds me of a mini-DVD player). It has a slot no. 2 which is for Game Boy cartridges (pretty cool feature). I don't buy Game Boy games for my son, but if I see them at garage sales and they are inexpensive, I will, but we mostly stick to Nintendo DS Games.
These are not cheap- but well worth the price. Walmart has them now for $129.99 (walmart.com) for Crimson Red, also in Cobalt Blue. This DS is significantly smaller than their original DS and lighter (to hold), that is why it is called "Lite". When you flip it closed, it automatically shuts the game down where you stopped at, and flip it open, the game is where you left it (as opposed to shutting the power down, that would stop the game where you saved it and start the game again at the beginning). The screen is colorful and bright, a HUGE difference to the old, old Game Boys if you remember those. I got ahold of one of those recently and had to squint to see the screen, so the graphics on this is AMAZING!
This console is 7.6 inches by 4.85 inches, and it is slim at 1.85 inches. I also just found out that when another kid has a DS and the same DS game inserted, that kids can play each other in their games for up to 30 feet away (I found this out this past weekend when my son and his cousin started playing each other on their separate DS's in the same room). It also comes with a microphone built in (for use with some games).
They have a new DS system out there now that is 3D, which seems cool, but in the meantime, these work very well for small kids up to teens (and even adults). My friends have bought this for their kids at age 3 to 4 and my son showed interest around then as well (I honestly think he would like this better than a handheld LeapPad). It's just pure entertainment and a little fun.